---
name: "floorf"
section: "3"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["linux", "freebsd"]
url: "https://new.carta.tech/floor"
---

# floorf(3)

largest integral value less than or equal to x

Part of [floor(3)](/floor/3.md).

## NAME

**floor**, **floorf**, **floorl** – largest integral value less than or equal to x

## LIBRARY

Math Library (libm, -lm)

## SYNOPSIS

**#include \<math.h\>**

*double*\

**floor**(*double x*);

*float*\

**floorf**(*float x*);

*long double*\

**floorl**(*long double x*);

## DESCRIPTION

The **floor**(), **floorf**() and **floorl**() functions return the largest integral value less than or equal to *x*, expressed as a floating-point number.

## SEE ALSO

[abs(3)](/abs/3.md), [ceil(3)](/ceil/3.md), [fabs(3)](/fabs/3.md), [ieee(3)](/ieee/3.md), [math(3)](/math/3.md), [rint(3)](/rint/3.md), [round(3)](/round/3.md), [trunc(3)](/trunc/3.md)

## STANDARDS

The **floor**() function conforms to ISO/IEC 9899:1990 (“ISO C90”). The **floorf**() and **floorl**() functions conform to ISO/IEC 9899:1999 (“ISO C99”).

## HISTORY

A **floor**() function first appeared in Version 5 AT&T UNIX.